Pushbutton switch with wear preventing groove

Abstract

A pushbutton switch includes a movable contact which effects an inverting motion in a case to get in and out of contact with a stationary contact to establish conduction and non-conduction of the switch. Grooves are provided along an inner bottom surface of the case so that free ends of the movable contact never scrape the inner bottom surface of the case upon an inverting motion of the movable contact.

What is claimed is: 
     
       1. In a pushbutton switch including a case having a closed bottom wall, said closed bottom wall having an inside surface located inside said case, said case also having one or more side walls adjacent and substantially perpendicular to said bottom wall, at least one first stationary contact located on the inside surface of said bottom wall, a second stationary contact located on the inside surface of said bottom wall, said second stationary contact not adjoining said first stationary contact, a movable contact having a peripheral supporting edge having a first section adjacent the inside surface of said bottom wall and a second section abutting said first stationary contact, said movable contact also having a central portion capable of contacting said second stationary contact by resilient deformation, an improvement comprising: the inside surface of said bottom wall defining at least one groove located directly adjacent said first section of said peripheral supporting edge such that said first section is suspended in or over said groove, thereby preventing said peripheral supporting edge from scraping along said inside surface of said bottom wall, the prevention of said scraping resulting in the prevention of a production of dust when said movable contact is deformed; wherein said movable contact comprises:   a flat rectangular leaf spring, wherein said peripheral supporting edge is divided into a pair of substantially parallel long edges defining a length and a pair of substantially parallel short edges defining a width,   said leaf spring bent along said length to form an arc,   said leaf spring defining a pair of substantially parallel slits disposed parallel to said long edges having ends adjacent said short edges, said pair of slits sectioning said leaf spring into a central fragment and a pair of side fragments, said central fragment capable of being deformed to contact said second stationary contact, and at least one of said side fragments being in contact with said first stationary contact;   wherein said short edges are disposed over said groove and said short edges do not contact said inside surface of said bottom wall.